Police are advising women not to walk alone at night if possible following an attack on a 19-year-old woman in Hertford Road, Hatfield.

They say it's too early to link the incident to a rape in the area earlier this month, but they are keeping an open mind as investigations continue.

Officers say that stranger attacks are rare in Hertfordshire, and say they are working hard to catch the man responsible, but they are encouraging women to be extra cautious.

They say that, if possible, women should walk with a friend, avoid dark alleyways or roads, always tell someone where they are going, and carry personal alarms that are easily accessible if needed to be used quickly.

In the latest incident a 19-year-old woman was grabbed from behind and punched in the face by a man in Hertford Road in Hatfield at 11.40pm on Sunday night, 25 April.

Detective Chief Inspector Mark Ross said the woman screamed and scared off the offender. She was not seriously injured.

"If she had not done so, we could be looking at a far more serious attack as we do not know what this manís intention was," he said.

According to the police, the offender is described as a white man, about 5' 10" tall, of large build, aged in his 30s with a round chubby face. He was wearing a dark blue coat with his hood up.

Police say the location of the latest attack is close to Mill Green where a 19-year-old woman was raped on Thursday 1 April, and although they say they are not in a position to formally link the attacks, they are keeping an open mind at this stage.

Anyone with any information in relation to this attack or knows who may be responsible is asked to contact police on 01707-354158 or Crimestoppers anonymously on 0800-555-111.